"When Donald Trump says things, it offends people sometimes and it can be controversial, but when Hillary makes mistakes, people die," McCain said.

She pointed to Iran's execution of nuclear scientist Shahram Amiri, who was allegedly a spy for the U.S. and who was apparently alluded to in some of Clinton's hacked emails.

"Why aren't we talking about this, talking about the fact that she put our national security at risk?" McCain wondered. "It's so egregious. This is real-life information about our CIA informants being murdered, and it's getting no coverage, except on this channel."